Question

Why is it impossible to measure both the position and the velocity of an electron

Answer 1

This is certainly not true for waves or electrons in general. The Heisenberg uncertainty principle states that the exact position and momentum of an electron cannot be simultaneously determined. This is because electrons simply don't have a definite position, and direction of motion, at the same time!

Answer 2

Electron is a microscopic particle. To know bout it's position or velocity, we incident light on it

Now to see a particle, it should:

1. Either has its own light, i.e, it emits its own light itself.
2. We incident light on it (externally)

In the case of an eletron (a microscopic particle), we incident light on it. which send it's flying.

(Why? Because it's mass is very less, 9.1×10^-31 kg!)

This is why it is impossible to measure both the position and velocity at the same time.

"Heisenberg tried using photons to locate electrons. Of course, when photons reach electrons, the electrons change velocity, and move to an excited state. As a result, it is impossible to precisely measure the velocity and location of an electron at the same time."

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